A 2500KVA AN/forced-air optional per project transformer supports medium-voltage to low-voltage distribution for industrial and large commercial projects.
At 2500 kVA, align voltage class, cooling, impedance, and documented losses with your single-line diagram and utility requirements before issuing an RFQ. This guide focuses on practical evaluation steps for buyers—measurement, documentation, and lifecycle support—not generic marketing claims.
Cross-check public catalog data on lbajiele.com and confirm project-specific limits with your utility or consulting engineer.
Contents
- Part 1. What a 2500KVA unit does in your network
- Part 2. Key specifications at 2500 kVA
- Part 3. Loading, environment, and compliance notes
- Part 4. Documentation and RFQ checklist
- Part 5. Commissioning, monitoring, and long-term operations
- Part 6. Product recommendation and Fit Boundary
- Part 7. Common specification mistakes
Part 1. What a 2500KVA unit does in your network
At 2500 kVA, the unit typically feeds larger motor plants, multi-building campuses, or utility secondary networks where fault level and voltage regulation matter.
Whether specified as power or distribution duty, nameplate kVA, tap range, and vector group are binding design inputs—not marketing labels.
Industrial buyers at this size class usually coordinate prospective fault current, downstream protection, and demand profile before finalizing transformer specifications.
Treat selection as a lifecycle decision: rated kVA, losses, and impedance should match documented site behavior after commissioning.
For related context, see the what is a dry type power transformer.
For related context, see the dry type distribution transformer installation.
Part 2. Key specifications at 2500 kVA
Fix primary class and secondary voltage on the approved single-line diagram before comparing vendor catalogs.
Include prospective fault level and relay coordination when reviewing impedance with your protection engineer.
LBAJI publishes catalog reference data for 10 kV SC(B)11-2500 (catalog reference) on the SC(B) resin insulated dry transformer series page. Treat the table below as a quotation starting point; issued drawings and type-test reports govern the final PO.
| Parameter | Catalog reference (2500 kVA) | Why it matters |
|---|---|---|
| Rated capacity | 2500 kVA | Continuous duty basis |
| No-load loss | 3.24 kW | Lifecycle energy cost |
| Load loss | 16.1 kW at 155°C (B) reference temperature | Thermal and efficiency planning |
| No-load current | 0.7% | Magnetizing design check |
| Short-circuit impedance | 6% | Protection coordination |
| Overall dimensions | 1520 × 1120 × 1760 mm (body); 1950 × 1500 × 2200 mm with shell | Civil and lifting planning |
| Weight | 4220 kg | Foundation and transport |
Typical voltage combinations on the public catalog include 6–11 kV class primary and 0.4 kV secondary with Dyn11 or Yyn0 groups and ±5% or ±2×2.5% tap ranges.
Confirm the exact combination required by your interconnection agreement.
Part 3. Loading, environment, and compliance notes
Loading above nameplate without documented approval can affect warranty and operating margin.
Harmonic-rich loads may require study before energization; record measured THD at the point of common coupling when motors and drives dominate the profile.
Altitude, ambient temperature, and enclosure influence derating. State elevation, average and maximum ambient, and indoor versus outdoor installation in every RFQ.
Fire separation, spill containment, or ventilation rules depend on local codes and the selected cooling class—confirm with the authority having jurisdiction before room layout freeze.
Buyers comparing bids should normalize loss figures at the same reference temperature and connection group. Importers often underestimate civil work because catalog weights exclude shipping crates, oil volume, or enclosure accessories that appear only on GA drawings.
When the feeder serves mixed motor and lighting load, document starting kVA or motor starting method so the supplier can comment on voltage dip—not only steady-state kVA. For campus projects, clarify whether one unit feeds multiple buildings or a single main switchboard; future tie-in plans affect impedance targets.
Maintenance planning should list oil sampling intervals for liquid-filled units or filter and fan service for ventilated dry-type rooms. Spare fuse, bushing, or fan lead times belong in the commercial review because they affect outage duration more than the core warranty term.
Training for local electricians should cover lockout/tagout around the primary disconnect, confined-space rules for vaults, and which alarms require immediate shutdown versus scheduled service. As-built records should tie nameplate photos to test reports so later upgrades do not rely on memory.
Utility account managers can clarify voltage tolerance bands and fault contribution limits; align witness tests with interconnection agreements before energization. If the project includes renewable generation, state whether the unit is a grid-facing step-down or a dedicated plant feeder so tap and protection assumptions stay consistent.
Part 4. Documentation and RFQ checklist
Use the checklist below as an RFQ attachment. Your EPC contract or utility may require additional items.
| Document / item | Purpose | When to request |
|---|---|---|
| Factory type or routine test report | Verify kVA, voltage, losses, impedance | Before purchase order |
| GA drawing and foundation load | Civil and lifting design | Design phase |
| Wiring / connection diagram | Termination and grounding | Before shipment |
| Loss and impedance certificate | Bid normalization | Tender comparison |
| Spare parts list | Bushings, gaskets, fans, sensors | Contract negotiation |
| Commissioning checklist | Ratio, polarity, grounding tests | Before energization |
RFQ inputs to include: primary and secondary voltage, vector group, tap range, altitude, ambient range, required cooling class, impedance target, delivery Incoterm, witness-test requirement, and language for nameplate markings.
Part 5. Commissioning, monitoring, and long-term operations
Commissioning should verify ratio, polarity, grounding, and protective relay coordination before loading the transformer to production demand.
Functional tests typically include insulation resistance and, for liquid-filled units, oil dielectric strength under agreed procedures.
After energization, monitor temperature, load profile, and abnormal gas or hot-spot trends according to manufacturer guidance.
Schedule post-warranty reviews when plant expansion is planned—2500 kVA feeders often need tap review within a few years of major load additions.
Maintain as-built single-line diagrams after feeder changes. Baseline load and temperature readings taken at commissioning simplify future troubleshooting.
Part 6. Product recommendation and Fit Boundary
Product recommendation: For 2500 kVA class projects, start engineering review with the SC(B) resin insulated dry transformer series and the broader transformer category.
| Better fit | Poor fit without extra study |
|---|---|
| Industrial/commercial MV-LV distribution with documented load | Unknown harmonic profile with no mitigation plan |
| Buyers who can supply SL diagram and protection data | Rush PO without voltage class confirmation |
| Projects accepting catalog-to-drawing confirmation cycle | Assumed utility approval without interconnection review |
Submit primary/secondary voltage, vector group, ambient conditions, altitude, and required test documents through Contact Us for model-specific confirmation.
Part 7. Common specification mistakes
- Comparing quotations that use different impedance bases or reference temperatures for losses.
- Using catalog weight for foundation design without the issued GA drawing.
- Ignoring altitude or ambient derating on outdoor installations.
- Selecting vector group without confirming grounding philosophy.
- Treating marketing brochures as substitutes for type-test or routine-test reports.
- Mixing 2500 kVA nameplate with downstream panel ratings that assume a different secondary voltage.
FAQ
What is a 2500KVA transformer used for?
It typically steps medium voltage to low-voltage distribution for industrial campuses, utility secondary networks, and large commercial plants at the 2500 kVA rating.
What cooling is typical at 2500 kVA?
Oil-immersed units commonly use ONAN; dry-type units rely on air ventilation with optional forced-air cooling for overload strategies—confirm on the datasheet.
What primary voltages are common?
Public LBAJI catalogs list 6–11 kV class primaries for many distribution units; confirm with your single-line diagram and utility rules.
What impedance should I expect?
Catalog reference for 2500 kVA is about 6%; verify with your protection study before final approval.
What documents should I request?
Type or routine test reports, GA drawings, wiring diagrams, loss certificates, tap data, and spare-parts lists.
Can this rating be used outdoors?
Oil-immersed pad-mount or substation styles are common outdoors where permitted; dry-type units need protected, ventilated rooms—match construction to site codes.
How do I compare dry type vs oil at this size?
Compare fire risk, maintenance, ventilation or oil containment, lifecycle losses, and indoor/outdoor constraints—not headline kVA alone.
